fbredius/storybook

const codeToKeyMap = {
  // event.code => event.key
  Space: ' ',
  Slash: '/',
  ArrowLeft: 'ArrowLeft',
  ArrowUp: 'ArrowUp',
  ArrowRight: 'ArrowRight',
  ArrowDown: 'ArrowDown',
  Escape: 'Escape',
  Enter: 'Enter',
};

interface Modifiers {
  alt?: boolean;
  ctrl?: boolean;
  meta?: boolean;
  shift?: boolean;
}

const allFalse = { alt: false, ctrl: false, meta: false, shift: false };

export const matchesModifiers = (modifiers: Modifiers | false, event: KeyboardEvent) => {
  const { alt, ctrl, meta, shift } = modifiers === false ? allFalse : modifiers;
  if (typeof alt === 'boolean' && alt !== event.altKey) return false;
  if (typeof ctrl === 'boolean' && ctrl !== event.ctrlKey) return false;
  if (typeof meta === 'boolean' && meta !== event.metaKey) return false;
  if (typeof shift === 'boolean' && shift !== event.shiftKey) return false;
  return true;
};

export const matchesKeyCode = (code: keyof typeof codeToKeyMap, event: KeyboardEvent) => {
  // event.code is preferable but not supported in IE
  return event.code ? event.code === code : event.key === codeToKeyMap[code];
};